PROC-1334: Simplify node replacement in rule filtering

Author: Joseph Barratt

proctor-common/src/main/java/com/indeed/proctor/common/el/filter/NodeHunter.java

@@ -1,6 +1,5 @@
 package com.indeed.proctor.common.el.filter;
 
-import com.google.common.collect.ImmutableList;
 import com.indeed.proctor.common.ProctorRuleFunctions.MaybeBool;
 import org.apache.el.parser.AstAnd;
 import org.apache.el.parser.AstFunction;
@@ -9,29 +8,18 @@
 import org.apache.el.parser.AstNot;
 import org.apache.el.parser.AstNotEqual;
 import org.apache.el.parser.AstOr;
-import org.apache.el.parser.ELParserTreeConstants;
 import org.apache.el.parser.Node;
 import org.apache.el.parser.NodeVisitor;
 import org.apache.el.parser.SimpleNode;
 
-import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
 import java.util.Collections;
 import java.util.IdentityHashMap;
-import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.Stack;
-import java.util.stream.Collectors;
 
 class NodeHunter implements NodeVisitor {
-    private static final List<String> NODE_TYPES = ImmutableList.copyOf(ELParserTreeConstants.jjtNodeName)
-            .stream()
-            .map(nodeName -> "Ast" + nodeName)
-            .collect(Collectors.toList());
-    private static final Map<String, Integer> NODE_TYPE_IDS = NODE_TYPES.stream()
-            .collect(Collectors.toMap(nodeType -> nodeType, NODE_TYPES::indexOf));
-
     private final Set<Node> initialUnknowns = Collections.newSetFromMap(new IdentityHashMap<>());
     private final Map<Node, Node> replacements = new IdentityHashMap<>();
     private final Set<String> variablesDefined;
@@ -125,21 +113,13 @@ private Node replaceNodes(
             }
             return newNode;
         }
-        final Class<?> nodeClass = node.getClass();
-        final Constructor<?> constructor = nodeClass.getConstructor(int.class);
-        final SimpleNode newNode = (SimpleNode) constructor.newInstance(NODE_TYPE_IDS.get(nodeClass.getSimpleName()));
-        for (int i = 0; i < node.jjtGetNumChildren(); i++) {
-            final Node newChild = replaceNodes(node.jjtGetChild(i));
-            newChild.jjtSetParent(newNode);
-            newNode.jjtAddChild(newChild, i);
-        }
-        newNode.jjtSetParent(node.jjtGetParent());
-        newNode.setImage(node.getImage());
-        if (newNode instanceof AstFunction) {
-            ((AstFunction) newNode).setPrefix(((AstFunction) node).getPrefix());
-            ((AstFunction) newNode).setLocalName(((AstFunction) node).getLocalName());
+        final SimpleNode asSimpleNode = (SimpleNode) node;
+        for (int i = 0; i < asSimpleNode.jjtGetNumChildren(); i++) {
+            final Node newChild = replaceNodes(asSimpleNode.jjtGetChild(i));
+            asSimpleNode.jjtAddChild(newChild, i);
+            newChild.jjtSetParent(asSimpleNode);
         }
-        return newNode;
+        return node;
     }
 
     @Override